The present application is directed to the movement of parcels. More particularly it is directed to a high-speed parcel handling system and method for unloading a container, such as a truck or trailer, of irregularly shaped and sized parcels, having a wide range of weights such as from a few ounces to 70 lbs. or more.
Also, even if the parcels are originally stacked in some pre-described order in a truck or trailer, as the truck or trailer moves, and hits speed bumps, makes turns, etc. the parcels shift, creating an unorganized accumulation within the container. For instance, a large box may be next to a small box, which is sitting on top of a mailing envelope. In other words, there is no true organization to the parcels having the large dynamic size, weight and shape differences. This situation makes achieving the goal of unpacking the parcels in an efficient manner, and placing them onto a conveyor belt at a high throughput difficult.
Presently, the most common way of unloading a container full of unorganized parcels is to have a human standing in the truck, picking and placing the parcels on the conveyor belt. It is understood that a person working alone in a container having 3,000 parcels can unload approximately 1,000 parcels in an hour, while two people working in the same container are able to move approximately 1,500 parcels in an hour. It is noted that adding still more people in a small area such as a container of a truck or trailer, the overall process slows down somewhat as the people need to stay out of each other's way. So even with two people working to remove 3,000 parcels from a shipping trailer, it would require 2 hours, whereas a single person would require 3 hours.
Automated parcel handling equipment does exist. An example of one such piece of equipment is vacuum moving block 100 shown in FIG. 1. As can be seen this is a large device having an overhead section 102 and a side section 104. The front faces of sections 102 and 104 each include a plurality of large suction cups 106. The vacuum moving block 100 is used to move large heavy objects. In operation, suction cups 106 on the overhead section 102 engage the top of a box being moved, and suction cups 106 on side section 104, (approximately a fixed 90° from the top section), engages a side of the same box. This allows the box to be picked up and moved to a different location. An issue with automated suction gripping device is that it is structured for large parcels and is not flexible in its use such that it can handle the dynamic size and shape range of parcels found, for example in the back of a shipping container.
If one would know that the parcels in a container were all of approximately the same size and weight, then a gripper arrangement such as shown in FIG. 1 could be sized to address the requirements. However, due to the varying sizes, shapes and weights of parcels found in a truck or trailer container, if the automated system is sized to grab the biggest and heaviest parcels, it would not be effective in moving smaller lighter parcels. Similarly, if sized to move small parcels it would be ineffective in moving the larger heavier parcels. Also if built to handle the larger parcels it would be a physically large system not allowing it to fit into a narrow area such as the interior of truck or trailer containers which are commonly anywhere from 10 to 26 feet deep with openings of 8 to 10 feet tall and 10 to 15 feet wide. Such fixed configuration systems would also be slow and clumsy in such a physically tight environment.
Therefore there is a need for an automated system and method to provide a high throughput movement of parcels from a truck or trailer container to a conveyor system, where the parcels have large dynamic range in the size, shape and weight, and where the parcels are in an un-organized state.